Ture and mechanic arts



March 23 ,1926.

A. MARS TON CONCRETE CONDUI'I' REENFORCEMENT Filed Sept. 12, 1924 lm an Patented Mar.

.iran: re

' Anson ARsToN, or AMES, IOWA, essrenon T IOWA STATE" COLLEGE or AGRICUL- TUBE AND MECHANIC ARTS, or AMES, IOWA, A CGBPORATION or IOWA.

CONCRETE-CONDUIT EEENFORGEMENT.

Application filed September 12, 1924. Serial No. 737,372

To allwhom 'z'tma-y concern:

Be it known thatI, Anson MAns'roN, a citizen of the UnitedStates, and a resident of Ames, in the county of Story and State I of Iowa, have-invented a certain new anduseful Concrete-Conduit Reenforcement, of

which the following is a specification.

The object of my invention is to pro- Vide a reenforcing device of simplefdura- Me andfineXpensive; construction that may be readily, quickly and easily applied to concrete conduits or the like, especially those with cross sections curved -circuinferentiallyv More specifically it is my object to pro-- 15 vide a reenforcement comprising a metallic body portiondesigned to be extended cir- "cumferentially through the concrete conduit and being provided with a series of radially extendedjaws rigidly secured 'to the body portion, and so arranged relative to the body portion and the concrete mate rial, that when pressure is applied to the concrete tending to distort it from its original curved shape, said radially extended jaws will tend to resist and oppose distortion of the reenforceinent from the original curve by adhesion and compression between them and thesolid concrete material, thereby opposing radial resisting forces to the -tendencyto distortion of the reenforcementfrom :the original curve, and whereby with a minimum 'amount of reenforcing metal the concrete conduitor the like may successfully resist such strains as would collapse and crack similar concrete structures reenforced with the ordinary reenforcingbars.

Myinvention consists in the construction being broken away and shown in section to illustrate the arrangement of my improved reenforcement in a conduit.

Figure 3 shows a side elevation of a concrete conduit with a portion thereof broken 'a short distance from the inner surface of a less curve.

Referring to the accompanying drawings, I have used the reference numeral 10 to indicate the body portion of the reenforcingbar. Formed integral with this body portion at both edges and preferably staggered, is a series of jaws 11 extended substantially at right angles to the body portion, and having their tips bent outwardly from the 101i gitudinal body 10. The width of each aw is preferably approximately equal to the space between two j aws, and these jaws have a length depending upon the curvature extending a substantial'distance into the concrete beyond the body portion 10. Q

The reference numeral 12 indicates a con crete-conduit of ordinary construction.

In applying my improved reenforcement to a concrete conduit, I preferably extend the body portion 10 circumferentially around the mold in which the conduit is to be formed, with its inner face spaced apart the mold; and then adjacent to the outer surface of the mold but spaced apart therefrom is an ordinary reenforcing bar 13, which may or may not be staggered with reference to the body portion l0. The outer reenforcing bar 18 must have suflicient iner bearing area" against the concrete to ure 8.

In practical use, and assuming that a CO11- 195 duit is provided with my improved reen forcenient as llustrated and described herein, and assuming further that a strain was applied to the top of the conduit, then obviously there would be a tendency to upper .j aw showniin Figure 5 could not have lengthen the curvature at the top of the ture, and in allinstauces any strains tending conduit and to shorten the curvature at the to distort the originalshape oi the'concrete opposite sides of. the conduit. In other would be resisted by the jaws exercising words, such strains would tend to distort adhesive and crushing strains upon the body the conduit into a substantially oval shape, of the concrete; I 70 the greatest-diameter ofwhich is in ap- I have determined by experimentthat proximately horizontal lines. lVhen such concrete conduitsreenforced 1n the manner strains are applied to my improved conduit 'herein disclosed and subjected to strains then on the parts thereof where thestrains suilicient to produce-the first visible crack in would tend to lengthen the curvature of the the conduit, will withstand substantially 7 body thetbody portion l()-.of the reentorcedouble the amount or strains ofasimilar oonment would tend to move: inwardly, as duits for-med with the kind ed ireenforce-am shown by the arrow tfi in Figuregtywhich unentsnow in-generalruse; A

movement? will be firmly resisted by thejaws I claim asmy'invention: a

11, whichagr-ip :the concrete by adhesion "1. An improvedeoncrete'striicture; corn-" Q,- a and compression againstvthe bent top and prising a vconcrete bodyga leenforoing bar between \the edges,.;as indicated by the arembedded therein .and having ta. series* of, rows 1 and h. \Vhere the strains would jaws extended; substantially at right angles? tend to shortenthe curvature,=as shownwin to the bar and rigidly-securedte-the bar, Figurej, the. reenforcen'ient would=te11d to said partsbeingso-shapedmm arranged- 25'! move toward the left, as shown by the arrow that when strainsare applied'to the con- 4 a in Figure v5, and toward the right as Crete body tending to zdistort it! iromsits shown by the arrows 7) in Figuieb; rThe ior-iginalshapeytlie free ends of-itherjaws will v strains tending-'to cause this curvatureiprovide, througlr adhesion toitheadjaeentir would (then tend to Inovathe' central: one of concrete body and eompressionagainstthe the jaws, shown in Figure 5, tOWiIlCh-tllflllGfi} adjacent concrete body, :firm iresistanceato-i as show-n -hyithe arrowWc and would also distortion. of the reenforcingbar frmnitstend to move the free end of the upper jaw original curvatures:

upwandlyeasshown by the arrow d in 2. An improved concrete structune,cem-1- Figure 5, and the free end of the lower jaw downwand-ly .as shown byithe arrow 0 in Figure Obviously, all ofuthese movements of the jaws wouldbe opposed'by the body of the concrete. For instancepthe embedded therein and havingva. seriessofr Us jaws extended isubstantiallyat. right angles Li: to the bar and rigidly; secured to the her, said parts being-sovshaped' and arranged that when strains are appliedto the concrete. 1 9 body tending toitdistortit from its original-n :..1 ing the concrete material adjacent to it, and shape,-the free endsofatheijaws will provide .5 the lower jaw could not more downwardly: through-adhesion tothe adjacent concrete i without crushing -.the,concretematerialadja body and con'ipressionuagainstthe. adjacent ent itdit aundeinedgep a V concrete body firm resistance tQdlStO-L'tiflll. 10D. In' the parts otthe conduitnwhere the of the reenforcingbar from-its original strains would tend ito cause thev outer bar 13 curvaturey and an! outer reenforeingibag a, to move inwardly, as shown by the arrow having suflicient innerrbearing-area against: is in Figure 5,.this movementwill be op the adjacenticoncretebody to'resist distorisrri posed \bydirect bearing, Ofwtllfidlllltil' face of tion inwardly from its original-,murvedfiW. the bar against the concreteavhich isof shape, said outer reenforoing be ;embedded..- sutficientjthiekness-undenithe bar 13,sately in the concrete body-substantially in-line it to resist such movement when the innera/raxlially from the first mentioned 'reenfore-h bearing area iseadequates ing bar'and having a relatively wide inner It isiwell known that concrete material bearing face, for the purposes, stated" 1-: has a very greatetliciency in resisting-crush An. improvedeoncreterstructure, com on ing strains but a imuch: less efiiciency in prising a'eoncretevbody,areenforcing ban be resisting tension-strains tending topull iitembedded therein and having-a serieseof: .1? apartu"lVithimyimprovementIhave taken jaws extended substantially at right angles-eh advantageof this great efiiciency of concretematerial in resistingcrushing strains and "said partsbeing so shaped-and errangedi,;-i. have so arranged -my reenforcement th-at that when strains areappliedito theconcrete- (A concrete provided with my improved re:-- body tending to distort it from its original,l- 1 enforcement cannot be distorted permanent; -sl1ape,-the free ends :oftthe. jaws will proly out of its original, shape unless such presvide,through adhesion to the adjacentroonsure and strains are applied to-it' as-will -crete-bodyiand compressionagainstthe a:d: overcome this great efiieiencyiof the conjacenticon-crete body, firm resistance. zto disdiscrete in overcoming crushing strains. tortion of the reenforcing barifnomiits origie, Obviously imy improvement may be apnal curvature, and anuouter. neenforoingbmrl i plied to concrete structures of any eurva having'suflicientinner hearing area iagainstoBQ,

its free end- Inoveiupwartlly .withoutwcrush p isi g -concretecbody, a reenfvorcing-ban 951i to the bar and rigidly. seeuredltriithe bar, 120

the adjacent concrete body to resist distor-. tion inwardly from its" original curved shape,

V 4.1111 improved reenforced concrete conduit, comprising a conduit body portion formed of concrete material and having a series 01' circumferentially arranged bars spaced apart from its inner circumference, said bars being formed with-jawsextended radially into the concrete body and rigidly connected to the reenforcing bars, said jaws having a Width ciroumferentially of the conduit much greater than their thickness longitudinally of the conduit, substantially as and for the purposes stated.

5. A reenforcernent device for concrete structures comprising a body portion and a series of jaws extended approximately at right angles thereto and rigidly secured to the body portion, the outer ends of said jaws being inclined away from the body portions of the jaws, for the purposes stated.

ANsoN MARSTON. 

